In this intervention study, researchers examined the effects of lycopene and green tea consumption on modulating prostate cancer risk.
The causal effects of metabolites modified by the intervention were further assessed by Mendelian randomization. In a sample of men with an elevated risk of prostate cancer, a 6-month intervention to increase lycopene intake was found to modify circulating levels of valine and pyruvate. MR analysis showed that genetically predicted increases in pyruvate increased prostate cancer risk, supporting a causal role for this particular metabolite in prostate cancer etiology. In this small trial, there was insufficient evidence to distinguish whether supplementation with green tea affected the metabolome.